Building Regulations

Building Regulations Part 1LA 2006

ELEMENT 2002 U Values (W/m²K) 2006 U Values (W/m²K) Typical Foam Depth mm 'A' Rated Builders (U Value) Others (U Value)
Horizontal Ceiling 0.16 0.13 120* 0.16 0.16
Pitched Roof Sloping Ceiling 0.20 0.16 150 0.20 0.18
Flat Roof 0.25 0.20 110 0.25 0.22
Walls 0.35 0.27 750.30 0.27
Floors0.250.2250 0.25 0.22
Sloping ceiling Loft Conversion0.300.201200.200.18

The 2006 Dwelling Emission Rate (DER) is currently set at 20% improvement over the 2002 Regulations. There is considerable complexity and flexibility in design criteria to meet carbon dioxide emission rates but the table below shows the best 'U' Value starting point to avoid too many iterations in showing compliance to SAP 2005.

The Scottish Building Regulations have fixed 'U' Value requirements according to whether or not the heating boiler is 'A' rated.

* Calculation based on unventilated loft space with 100mm mineral fibre at loft floor level. Air leakage not to exceed 10m³/m²/hr @ 50Pa